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Hitachi EX 100-3 fuel Issue

bluetick

Well-Known Member
Joined
Feb 6, 2011
Messages
81
Location
north carolina
Hello all,I have a EX 100-3 that seems to have developed a fuel problem. Machine was running fine then started sputtering and die. Remove fuel filter, it was half empty, filled a new one and installed it and machine worked fine for about 15 mins. same issue,machine died again pull fuel filter, half empty refilled and installed. Same issue, but this I pumped the manual pump , machine started again but eventually died any suggestion would be greatly appreciated. Thxz
 

GrandpaScott

Active Member
Joined
Sep 22, 2011
Messages
25
Location
Minnesota
Occupation
Septic System Designer/Installer/Inspector
I just got one of my EX 60's home after the same type of symptoms. I did same, replaced fuel filter, and added some JB Fuel additive (the type you'd use in winter for antigel), and that helped for a while. Mine would throttle up, but when it took the load, it would run real bad. I had to move from the "E" throttle position to the "I" position, and I could get enough fuel moving through to function. I took it home, changed the filter again, added some more of the JB and ran it for about a half hour, seemed OK, so I took it back out on the job. Happened again :mad: so I called Justice Brothers and they recommended a different conditioner than I had used. I drained the fuel tank, and put about 10 gallons of fuel back in. Still no go, and now the machine was dead (this was last fall). I put my other machine to work to finish the season, so the one that was down sat for the winter. I went back, added another 10 gallons of fuel, and hit the engine with some ether (my intake heater had failed years ago, and was not hooked up, so be sure to disconnect your's), and it fired (ether was to verify working engine). So I drained the bottom 5 gallons of fuel, to ensure no water in tank, and it was good there. It was still acting a little funny, so I also drained the fuel line, which did have water in it. Knock on wood, I'm operating again. The fuel line seemed to have been the remaining issue. I suppose it, being at the bottom of the system, can hold some water, and was probably mixing it back in.

Good luck!
 

Delmer

Senior Member
Joined
Jan 3, 2013
Messages
8,864
Location
WI
Do you have a sediment trap and water remover? Check for that and clean it. The Japanese like to put a screen INSIDE the banjo bolt on the intake to the transfer pump from the fuel tank, IF there's no water separator screen, then that tiny screen is the place that all that big junk stops, it doesn't stand a chance. Take the banjo bolt out, unscrew the screen, tap it out and put it back in.
 

Tones

Senior Member
Joined
Mar 15, 2009
Messages
3,059
Location
Ubique
Occupation
Ex land clearing contractor, part-time retired
And if it still won't run after Delmers suggestions then check the screen in the fuel tank.
 

thepumpguysc

Senior Member
Joined
Mar 18, 2010
Messages
7,445
Location
Sunny South Carolina
Occupation
Master Inj.Pump rebuilder
I have an injection pump sitting on my bench RIGHT NOW..
Complaint was, dies/looses power after getting warm..
1st thing I did was pulled the banjo bolt out of the supply pump INLET, under/below the hand primer..
SLAM FULL OF ****.. mostly bugs & twigs..?? The problem coulda been fixed over the phone or AT THE FRONT COUNTER but my shop foreman is an ass..
SO.. 800.00 later & another day to order mounting gaskets & he'll be runnin tomorrow..
I "tweeked" the fuel to 10% over & 50 rpm on the governor/100 engine JUST SO, he "THINKS" he got something for 800.00. GOD, I hate my day job..
CHECK the banjo bolt below the hand primer..
 

Randy88

Senior Member
Joined
Feb 2, 2009
Messages
2,149
Location
iowa
Everyone hates those screw in strainers, I like them, they plug first and are easy to clean and it sure saves putting in fuel filters all the time, when the machines slows down or loses power, you just clean the screen and don't have to prime the fuel system at all, hit full throttle and let it sit upon startup and in a few minutes fuel is purged through everything and your back up and running again. I've blown those screens out dozens of times to every filter change, without them in, we're constantly changing filters and having to prime the engine again each time.
 

Delmer

Senior Member
Joined
Jan 3, 2013
Messages
8,864
Location
WI
Exactly Randy

And they're meant to be used with a water separator that has a mesh cylinder big enough to confuse with a bug zapper, if you manage to plug those up then you really have more serious problems than an engine bogging down.
 

Bc18

New Member
Joined
Aug 1, 2016
Messages
4
Location
Southern California
Sounds like you're sucking air in the system. I don't know how the fuel system is set up on unit but I would start by checking fuel psi on the delivery side to the injection pump. I see a lot of priming plungers go bad and suck air through there.

I know it sounds stupid but I have to ask is the fuel level in the tank accurate with the fuel gauge.
 

GrandpaScott

Active Member
Joined
Sep 22, 2011
Messages
25
Location
Minnesota
Occupation
Septic System Designer/Installer/Inspector
So, I was a bit too optimistic with my earlier post. The machine ran good for a couple of hours, then back in the crapper. I called the service department and the guy said maybe it was an air-leak, so suction might be affected. I decided to try to change the fuel line, so I dropped the cover under the machine to get at the inlet to the transfer pump, and being underneath the machine, I saw that the nipple for the fuel line was part of another banjo fitting. It was at that moment that I realized that Delmer nailed it in his June 13 post. I'd been told about the screen in the banjo bolt, but never found the right one (I'd been checking all of the banjos that I could get to from the top of the motor. I guess, in hindsight, that makes the most sense to have the first point of inlet screened, which it was. That sucker was plugged full of crap. I cleaned it out, blew it out, and put it back in service, gave the manual plunger about 20 pumps, and the machine fired back up, and ran all day.
 

GrandpaScott

Active Member
Joined
Sep 22, 2011
Messages
25
Location
Minnesota
Occupation
Septic System Designer/Installer/Inspector
Do you have a sediment trap and water remover? Check for that and clean it. The Japanese like to put a screen INSIDE the banjo bolt on the intake to the transfer pump from the fuel tank, IF there's no water separator screen, then that tiny screen is the place that all that big junk stops, it doesn't stand a chance. Take the banjo bolt out, unscrew the screen, tap it out and put it back in.
You nailed it! Thanks for knowing what to look for!
 

Ronsii

Senior Member
Joined
Jun 26, 2011
Messages
3,464
Location
Western Washington
Occupation
s/e Heavy equipment operator
You may want to periodically check and clean that screen before the motor starts sputtering, we finally drained the fuel tank and got in there with a shopvac and small extension hose to remove the years of crud buildup... before that we would be cleaning the screen every couple hours or more if the tank was low on fuel.
 

bluetick

Well-Known Member
Joined
Feb 6, 2011
Messages
81
Location
north carolina
Thanks to all who have replied to my post,some very good advise has been posted. I will be removing the banjo filter on the inlet side of the transfer pump as this is the only thing other than draining fuel tank I have not tried.,
Thanks again
 

Tones

Senior Member
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Mar 15, 2009
Messages
3,059
Location
Ubique
Occupation
Ex land clearing contractor, part-time retired
Just one further thing for people who read this thread, if everything that has been written here checks out OK then replace the nilon valves in the transfer pump. With age they become pitted and won't seat properly. A kit costs just a few bucks and is a job most of you can do.
Gota love simple fixes bluetick:)
 

John Shipp

Senior Member
Joined
Mar 5, 2015
Messages
641
Location
England
Occupation
forestry contracting
Sometimes not only the banjo screen is blocked, but the whole fuel line system can be lined with crap. Some of these machines run over 30 feet of 3/8" rubber hose before getting to the engine, just to position filters inside a door etc, I've ended up changing these hoses before and been amazed how much crud is weighing them down. Get one tiny pinprick hole up by the lift pump where the hose bends, and you'll not even get half a filter full...
 

Delmer

Senior Member
Joined
Jan 3, 2013
Messages
8,864
Location
WI
Could have been more clear for GrandpaScott. I forgot to add that the little b*****d we're talking about is the one pointing straight down, from the BOTTOM of the transfer pump. At least all the ones I've seen. There's only one hardest place to find, and that's where it is. It's logical if you follow the lines from the tank, to water separator, to transfer pump, to filter and back to injection pump. Sometimes you can't see all that stuff though.
 
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